Calendar having a displaceable support cylinder

ABSTRACT

The support cylinder for the rolls includes a roll barrel which is displaceable under the influence of a hydrostatic support element. Upon opening of the calendar, the support element is permitted to move a distance equal to the sum of the maximum gaps between the opened rolls.

United States Patent Lehmann May 20, 1975 CALENDAR HAVING A DISPLACEABLE [56] References Cited SUPPORT CYLINDER UNITED STATES PATENTS [75] Inventor: Rolf Lehmann, Muts hell n, 3,016,8l9 1 1962 Kupka 100/163 Switzerland 3,340,796 9/1967 Link z [73] Assignee: Escher Wyss Limited, Zurich, 3369483 H968 Muller loo/70 X Swltzedand Primary ExaminerBilly 1. Wilhite [22] Filed: Mar. 27, 1974 Attorney, Agent, or Firm-Kenyon & Kenyon Reilly 21 App]. No.: 455,357 &

30 Foreign Application Priority Data [57] ABSTRACT Apr. 17 1973 Switzerland 5452/73 The Support cylinder for the T0115 includes a roll barrel which is displaceable under the influence of a hydro- 52 us. c1. 100/163 R; 100/170 Static Support element Upon Opening of the calendar, 51 int. Cl B30b 3/04 the Support element is Permitted to move a distance 58 Field at Search 100/161, 162 R, 163 R, equal to the Sum of the maximum p between the 100/164, 165, 166, 168, 169, 170; 425 367; Opened rolls- 3 Claims, 2 Drawing Figures CALENDAR HAVING A DISPLACEABLE SUPPORT CYLINDER This invention relates to a calendar and particularly to a calendar having a plurality of superjacent rolls and a pressure cylinder which acts as a bottom roll.

Calendars having superjacent rolls and pressure cylinders acting as a bottom roll have been known. However, complicated pressure mechanisms have been used to press the bottom roll against the superjacent rolls in order to provide the total contact pressure between the individual rolls. Further, many of these calendars have experienced a difficulty in that they do not permit a sufficiently rapid load relief of the rolls which is required for a rapid opening of the calendar. As a result, additional mechanisms have been required to permit a rapid opening of the calendars. This, in turn, has resulted in the calendars becoming more complicated, expensive and troubleprone.

Accordingly, it is an object of the invention to provide a simplified reliable calendar.

It is another object of the invention to provide a calendar which permits the formation of a line pressure between individual rolls which is more uniform than previously possible.

It is another object of the invention to provide a calendar which can be rapidly opened.

Briefly, the invention provides a calendar comprising a plurality of superjacent rolls which are mounted for movement away from each other to form gaps therebetween upon opening of the calendar and a pressure cylinder under the rolls. The pressure cylinder includes a stationary support member, a roll barrel rotatably mounted about the support member to support the rolls, and at least one hydrostatic support element supporting the roll barrel on the support member. The hydrostatic support element is displaceable to permit movement of the roll barrel away from the rolls over a distance equal to an amount at least equal to the sum of the maximum gaps between the rolls upon opening of the calendar.

In order to displace the hydrostatic support element, a first means is provided for moving the element over a distance equal to an amount at least equal to the sum of the gaps between the rolls. This means is effective upon closing of the calendar to move the roll barrel into supporting relation with the rolls. In addition, a second means is provided for permitting the support element to move over this distance away from the rolls upon opening of the calendar. In this embodiment, the first means is in the form of a hydraulic system for lifting the support element from the support member towards the rolls while the second means is a valve within the hydraulic system for venting the system to permit movement of the support element away from the rolls.

In order to support the rolls, a suitable support means is provided for each roll to support each in spaced relation to each other to define gaps of predetermined size upon opening of the calendar.

These and other objects and advantages of the invention will become more apparent from the following detailed description and appended claims taken in conjunction with the accompanying drawings in which:

FIG. 1 illustrates a side view and a partial sectional view of a calendar according to the invention; and

FIG. 2 diagrammatically illustrates the gaps between the individual rolls upon opening of the calender.

Referring to FIG. 1, the calendar includes a stand 1 which may be constructed as a frame and which contains, for example, two vertical side parts 1. Each of these side parts 1 is provided with a guide 2 on which bearing housings 3, 4, 5, 6 of rolls 7, 8, 9, 10 are mounted in superjacent relation. The bearing housings 36 are adjustable along the respective guides 2 in any suitable manner and, in turn, are each provided with guides 11 in which bearing blocks 12 of the individual rolls 710 are guided. Each bearing block 12 contains a bearing 13 in which a trunnion of a roll 7l0 is rotat-v ably supported. Further details of the bearing blocks 12 are described in US. patent application Ser. No. 455,301 filed Mar. 27, 1974. A support means, in the form of a stop abutment screw 15, is also provided in each bearing housing 36 to limit downward motion of the bearing blocks 12 and to support the rolls in spaced relation to each other to define gaps S of predetermined size upon opening of the calendar. These stop abutment screws 15 are adjustable to vary the gaps S between the individual rolls 710 as shown in FIG. 2 when the calendar is open.

The calendar also has a pressure cylinder 16 which serves as a bottom roll. This cylinder 16 contains a stationary support element 17 which is mounted on pedestals 18 which, in turn, are mounted on the stand 1. The cylinder also includes a roll barrel 20 which is carried on hydrostatic support elements 21 and which is rotatable about the support member 17 to support the rolls 7l0 upon closing of the calendar. The hydrostatic support elements 21 are in the form of pistons which are guided in cylinder bores 22 of the support member 17. In order to lift the support elements 21, a means such as a hydraulic system is connected into the bores 22. This system includes a duct 23 which communicates each bore 22 with a reservoir 25 of hydraulic medium and a pump 24 in the duct 23 for pumping the hydraulic medium into the bore 22. Return ducts (not shown) are also used to return any medium which discharges from leakage points in the system to the reservoir. The lifting of the support elements 21 causes the roll barrel 20 to move towards the rolls 710 and to lift and press the rolls 710 together to establish a substantially uniform line pressure between the rolls 710 and cylinder 16.

In order to permit the hydrostatic support element 21 to descend, a means such as a three way valve 26 or other change over element is disposed in the duct 23 of the hydraulic system downstream of the pump 24 for venting the system. The three way valve 26 enables the pump 24 to be disconnected from the cylinder bores 22 and connected to the reservoir 25. In this case, the hydraulic support elements 21 descend into the lowest positions so that the calendar opens. The maximum displacement of the support element 21 is greater than the sum of the possible gaps S between the individual rolls 710 and cylinder 16 when the calendar is open.

Referring to FIG. 2, the gaps S which are assumed to be identical in the interests of simplicity, but which may also be unequal, are disposed between the rolls 7, 8, 9, 10 and the cylinder 16 (which acts as a bottom roll) when the calendar is open. The gaps S are defined by adjustment of the individual stop abutment screws 15. The stop adjustment screw 15 of the roll 10 must be adjusted so as to permit the roll to descend by the distance 38 (FIG. 1). The roll barrel 20 of the bottom roll 16 is then lowered by the amount 48. It is to be noted that these values are only examples and apply to a calendar with five rolls and identical gaps S when the calendar is open.

The maximum displacement of the support elements 21 must amount to 48 if gaps of the desired magnitude are to be obtained. However, the maximum displacement may preferably be greater. In this case, a stop abutment, which is not shown, is provided for the barre] 20 if the magnitude of the gap between the rolls and 16 is to be adjustable.

As a rule, the roll barrel 20 is supported on an entire series of support elements 21. It is, however, also possible for a single strip shaped support element to be used which extends along a substantial part of the axial length of the barrel 20. Finally, the support elements 21 can be constructed in a manner (not shown) in which a lubricant film is formed between their upper support surface and the barrel 20.

What is claimed is:

1. A calendar comprising a plurality of superjacent rolls, said rolls being mounted for movement away from each other to form gaps therebetween upon opening of the calendar; and

a pressure cylinder disposed under said rolls, said cylinder including a stationary support member, a roll barrel rotatably mounted about said support memher to support said rolls and at least one hydrostatic support element supporting said roll barrel on said support member, said hydrostatic support element being displaceable to permit movement of said roll barrel away from said rolls over a distance equal to an amount at least equal to the sum of the maximum gaps between said superjacent rolls upon opening of the calendar.

2. A calendar comprising a plurality of superjacent rolls,

support means for supporting each roll in spaced relation to each other to define gaps of predetermined size therebetween upon opening of the calendar,

a pressure cylinder disposed beneath said rolls, said cylinder including a support member, a roll barrel rotatably mounted about said support member to support said rolls upon closing of the calendar, and at least one hydrostatic support element supporting said roll barrel on said support member,

first means for moving said hydrostatic support element over a distance equal to an amount at least equal to the sum of said gaps between said superjacent rolls to move said roll barrel into supporting relation with said rolls upon closing of the calendar, and

second means for permitting said hydrostatic support element to move over said distance upon opening of the calendar.

3. A calendar as set forth in claim 2 wherein said first means includes a hydraulic system for lifting said support element from said support member towards said superjacent rolls, and said second means includes a valve in said hydraulic system for venting said system to permit movement of said support element away from said superjacent rolls. 

1. A calendar comprising a plurality of superjacent rolls, said rolls being mounted for movement away from each other to form gaps therebetween upon opening of the calendar; and a pressure cylinder disposed under said rolls, said cylinder including a stationary support member, a roll barrel rotatably mounted about said support member to support said rolls and at least one hydrostatic support element supporting said roll barrel on said support member, said hydrostatic support element being displaceable to permit movement of said roll barrel away from said rolls over a distance equal to an amount at least equal to the sum of the maximum gaps between said superjacent rolls upon opening of the calendar.
 2. A calendar comprising a plurality of superjacent rolls, support means for supporting each roll in spaced relation to each other to define gaps of predetermined size therebetween upon opening of the calendar, a pressure cylinder disposed beneath said rolls, said cylinder including a support member, a roll barrel rotatably mounted about said support member to support said rolls upon closing of the calendar, and at least one hydrostatic support element supporting said roll barrel on said support member, first means for moving said hydrostatic support element over a distance equal to an amount at least equal to the sum of said gaps between said superjacent rolls to move said roll barrel into supporting relation with said rolls upon closing of the calendar, and second means for permitting said hydrostatic support element to move over said distance upon opening of the calendar.
 3. A calendar as set forth in claim 2 wherein said first means includes a hydraulic system for lifting said support element from said support member towards said superjacent rolls, and said second means includes a valve in said hydraulic system for venting said system to permit movement of said support element away from said superjacent rolls. 